Sterile containers, also called sterilization containers, comprise, as a rule, a box-shaped, lower container part and a container cover that can be placed tightly thereon. Such sterilization containers are known to be used to sterilize medical devices. The complete sterilization container is heated, as a rule, during the sterilization process, so that a diverse overpressure develops within the container. To make it possible to reduce this overpressure, such sterilization containers are provided in a wall area or in a plurality of wall areas with ventilation openings, through which the exchange of air with the surrounding area takes place.
To bring about sterilization of the entering ambient air especially during the cooling phase, during which ambient air enters the sterilization container for pressure equalization, such sterilization containers are usually equipped with a so-called sterile barrier. An air-permeable filter sheet, which fully covers the ventilation openings, is used as a sterile barrier in some embodiment variants. Various constructions, in which an air-permeable pressing disk is used to hold the filter sheet, are known in the state of the art for fixing such a filter sheet in the wall area of the ventilation openings tightly and sealingly.
Reference should be made in this connection, for example, to DE 20 2010 009 925 U1. A frame element, which has a ring-shaped design and is arranged stationarily in the area surrounding the ventilation openings within the corresponding wall area, is used in this constructions. The pressing disk has various perforations in this construction, so that the pressing disk itself is likewise permeable to air. A flat spring, which is provided with bayonet connection elements, is provided in this construction to hold the pressing disk or for pressing against the filter sheet placed on the inner wall in the area of the ventilation openings. The flat spring can be meshed and unmeshed with correspondingly associated bayonet connection elements of the frame element by means of these bayonet connection elements. Furthermore, the flat spring can be rotated about a common central axis of rotation in relation to the pressing disk, and the pressing disk is held in the frame element nonrotatably during the rotary adjustment of the flat spring.
Thus, a plurality of components are used in this construction to press the filter sheet stationarily against the inner wall of the wall area with the ventilation openings.
Furthermore, another construction, in which the pressing disk presses the filter sheet on the top side by means of special locking connections via a ball catch connection, is known from DE 20 2011 001 772 U1. The pressing disk is designed as a round disk in this construction and has a circular locking groove on the outside, with which the pressing disk can be brought lockingly in connection with locking elements.
These locking elements are arranged for this in the circumferential area of the ventilation openings and thus of the mounted pressing disk in a uniformly distributed pattern. Each locking element is designed as a separate component and arranged stationarily in mounting holes of ring segments projecting axially over the wall area extending at right angles to the wall area.
The locking elements are formed from an approximately cylindrical housing block, which is provided with a radial hole extending at right angles. A locking ball, which meshes (engages) radially inwardly with the locking groove of the pressing disk in the mounted state, is received in the radial hole adjustably in a spring-loaded manner. The housing block of the locking element is fixed stationarily in the respective mounting hole, for example, by means of a spring-type straight pin.
It is advantageous according to the devices of DE 20 2010 009 925 U1 and DE 20 2011 001 772 U1 that the pressing disk can be pressed onto the filter sheet without the pressing disk having to be rotated for fixation relative to the filter sheet, as this is known from the state of the art for previous constructions.
However, as it was already mentioned above, these constructions for holding the pressing disk have very complicated designs. The handling of the bayonet connections is also relatively unfavorable in DE 20 2010 009 925 U1, because the flat spring must first be aligned concentrically with the frame element and in the circumferential direction with its bayonet connection elements with the bayonet connection elements of the frame element for establishing these connections manually in order to be subsequently able to be rotated relative to the frame element.
It is additionally necessary in the subject of DE 20 2011 001 772 U1 to provide the pressing disk with a radially extending grip part, which must be located at a spaced location from the wall area of the sterilization container in order to make it possible to reach behind it. It shall be achieved by means of this grip part that the fingers can reach behind the pressing disk, so that the locking connections between the pressing disk and the locking balls can be released in a simple manner. The locking connections can be released by themselves in unfavorable cases in case of an impact on the container cover.